The ramifications of the average human being able to learn more in less time are relatively gigantic. So gigantic, in fact, that I think they dwarf what small social-inequity considerations are raised (if it can really be done for a $90 kit right off the bat, then just wait until economies of scale kick in).
I'm all for allowing drug use of any kind into professional sports. I think it's silly that we watch rather grotesque caricatures of humans swinging bats or tackling people, then pretend to be shocked and admonish them when we find out they're "cheating" by using chemicals. As if the health risks associated with steroids and HGH somehow outweigh the simple risks of broken bones and mutilated joints that are a direct consequence of pushing a body to its limits and beyond on a daily basis.